Andrew Boyson / net

A stack which works with or without an Mbed os library. Provides IPv4 or IPv6 with a full 1500 byte buffer.

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udp/dns/dnsquery.c@172:9bc3c7b2cca1, 2020-12-16 (annotated)

Committer:
andrewboyson
Date:
Wed Dec 16 17:33:22 2020 +0000
Revision:
172:9bc3c7b2cca1
Parent:
171:f708d6776752
Child:
173:9bc30cd82a76
Modified name resolution to work with both IPv4 and IPv6. Before there were two independent modules.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 61:aad055f1b0d1 1 #include <stdint.h>
andrewboyson 61:aad055f1b0d1 2 #include <stdbool.h>
andrewboyson 61:aad055f1b0d1 3
andrewboyson 13:9cd54f7db57a 4 #include "log.h"
andrewboyson 93:580fc113d9e9 5 #include "mstimer.h"
andrewboyson 13:9cd54f7db57a 6 #include "net.h"
andrewboyson 37:793b39683406 7 #include "action.h"
andrewboyson 49:1a6336f2b3f9 8 #include "ip4addr.h"
andrewboyson 49:1a6336f2b3f9 9 #include "ip6addr.h"
andrewboyson 13:9cd54f7db57a 10 #include "dhcp.h"
andrewboyson 13:9cd54f7db57a 11 #include "dns.h"
andrewboyson 13:9cd54f7db57a 12 #include "udp.h"
andrewboyson 172:9bc3c7b2cca1 13 #include "eth.h"
andrewboyson 13:9cd54f7db57a 14 #include "slaac.h"
andrewboyson 13:9cd54f7db57a 15 #include "dnshdr.h"
andrewboyson 13:9cd54f7db57a 16 #include "dnsname.h"
andrewboyson 128:79052cb4a41c 17 #include "dnslabel.h"
andrewboyson 13:9cd54f7db57a 18
andrewboyson 37:793b39683406 19 bool DnsQueryTrace = false;
andrewboyson 13:9cd54f7db57a 20
andrewboyson 93:580fc113d9e9 21 #define TIME_OUT_SENT_MS 3000
andrewboyson 13:9cd54f7db57a 22
andrewboyson 13:9cd54f7db57a 23 #define MDNS_UNICAST false
andrewboyson 13:9cd54f7db57a 24
andrewboyson 35:93c39d260a83 25 char DnsQueryName[DNS_MAX_LABEL_LENGTH+1];
andrewboyson 13:9cd54f7db57a 26 uint32_t DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 27 char DnsQueryIp6[16];
andrewboyson 30:e34173b7585c 28 bool DnsQueryIsBusy = false;
andrewboyson 13:9cd54f7db57a 29
andrewboyson 171:f708d6776752 30 static char _RecordType = DNS_RECORD_NONE;
andrewboyson 171:f708d6776752 31 static int _DnsProtocol = DNS_PROTOCOL_NONE;
andrewboyson 171:f708d6776752 32 static int _IpProtocol = 0;
andrewboyson 171:f708d6776752 33 static uint32_t _StartedMs = 0;
andrewboyson 171:f708d6776752 34
andrewboyson 13:9cd54f7db57a 35 static void reap()
andrewboyson 13:9cd54f7db57a 36 {
andrewboyson 13:9cd54f7db57a 37 if (!DnsQueryIsBusy) return;
andrewboyson 13:9cd54f7db57a 38
andrewboyson 171:f708d6776752 39 if (MsTimerRelative(_StartedMs, TIME_OUT_SENT_MS))
andrewboyson 13:9cd54f7db57a 40 {
andrewboyson 13:9cd54f7db57a 41 LogTimeF("DNS reaped ongoing request for ");
andrewboyson 13:9cd54f7db57a 42 if (DnsQueryName[0]) LogF("name %s", DnsQueryName);
andrewboyson 13:9cd54f7db57a 43 if (DnsQueryIp4)
andrewboyson 13:9cd54f7db57a 44 {
andrewboyson 47:73af5c0b0dc2 45 Log("ip4 "); Ip4AddressLog(DnsQueryIp4);
andrewboyson 13:9cd54f7db57a 46 }
andrewboyson 13:9cd54f7db57a 47 if (DnsQueryIp6[0])
andrewboyson 13:9cd54f7db57a 48 {
andrewboyson 172:9bc3c7b2cca1 49 Log("ip6 "); Ip6AddrLog(DnsQueryIp6);
andrewboyson 13:9cd54f7db57a 50 }
andrewboyson 13:9cd54f7db57a 51 LogF("\r\n");
andrewboyson 13:9cd54f7db57a 52
andrewboyson 13:9cd54f7db57a 53 DnsQueryName[0] = 0;
andrewboyson 13:9cd54f7db57a 54 DnsQueryIp4 = 0;
andrewboyson 13:9cd54f7db57a 55 DnsQueryIp6[0] = 0;
andrewboyson 13:9cd54f7db57a 56 DnsQueryIsBusy = false;
andrewboyson 171:f708d6776752 57 _StartedMs = MsTimerCount;
andrewboyson 171:f708d6776752 58 _DnsProtocol = DNS_PROTOCOL_NONE;
andrewboyson 171:f708d6776752 59 _IpProtocol = 0;
andrewboyson 171:f708d6776752 60 _RecordType = DNS_RECORD_NONE;
andrewboyson 13:9cd54f7db57a 61 }
andrewboyson 13:9cd54f7db57a 62 }
andrewboyson 43:bc028d5a6424 63 void DnsQueryMain()
andrewboyson 13:9cd54f7db57a 64 {
andrewboyson 93:580fc113d9e9 65 reap();
andrewboyson 13:9cd54f7db57a 66 }
andrewboyson 171:f708d6776752 67 void DnsQueryIp4FromName(char * name, int dnsProtocol, int ipProtocol)
andrewboyson 13:9cd54f7db57a 68 {
andrewboyson 171:f708d6776752 69 DnsLabelMakeFullNameFromName(dnsProtocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 171:f708d6776752 70 DnsQueryIp4 = 0;
andrewboyson 171:f708d6776752 71 DnsQueryIp6[0] = 0;
andrewboyson 171:f708d6776752 72 DnsQueryIsBusy = true;
andrewboyson 171:f708d6776752 73 _StartedMs = MsTimerCount;
andrewboyson 171:f708d6776752 74 _DnsProtocol = dnsProtocol;
andrewboyson 171:f708d6776752 75 _IpProtocol = ipProtocol;
andrewboyson 171:f708d6776752 76 _RecordType = DNS_RECORD_A;
andrewboyson 13:9cd54f7db57a 77 }
andrewboyson 171:f708d6776752 78 void DnsQueryIp6FromName(char * name, int dnsProtocol, int ipProtocol)
andrewboyson 13:9cd54f7db57a 79 {
andrewboyson 171:f708d6776752 80 DnsLabelMakeFullNameFromName(dnsProtocol, name, sizeof(DnsQueryName), DnsQueryName);
andrewboyson 171:f708d6776752 81 DnsQueryIp4 = 0;
andrewboyson 171:f708d6776752 82 DnsQueryIp6[0] = 0;
andrewboyson 171:f708d6776752 83 DnsQueryIsBusy = true;
andrewboyson 171:f708d6776752 84 _StartedMs = MsTimerCount;
andrewboyson 171:f708d6776752 85 _DnsProtocol = dnsProtocol;
andrewboyson 171:f708d6776752 86 _IpProtocol = ipProtocol;
andrewboyson 171:f708d6776752 87 _RecordType = DNS_RECORD_AAAA;
andrewboyson 13:9cd54f7db57a 88 }
andrewboyson 171:f708d6776752 89 void DnsQueryNameFromIp4(uint32_t ip, int dnsProtocol, int ipProtocol)
andrewboyson 13:9cd54f7db57a 90 {
andrewboyson 171:f708d6776752 91 DnsQueryName[0] = 0;
andrewboyson 171:f708d6776752 92 DnsQueryIp4 = ip;
andrewboyson 171:f708d6776752 93 DnsQueryIp6[0] = 0;
andrewboyson 171:f708d6776752 94 DnsQueryIsBusy = true;
andrewboyson 171:f708d6776752 95 _StartedMs = MsTimerCount;
andrewboyson 171:f708d6776752 96 _DnsProtocol = dnsProtocol;
andrewboyson 171:f708d6776752 97 _IpProtocol = ipProtocol;
andrewboyson 171:f708d6776752 98 _RecordType = DNS_RECORD_PTR;
andrewboyson 13:9cd54f7db57a 99 }
andrewboyson 171:f708d6776752 100 void DnsQueryNameFromIp6(char* ip, int dnsProtocol, int ipProtocol)
andrewboyson 13:9cd54f7db57a 101 {
andrewboyson 171:f708d6776752 102 DnsQueryName[0] = 0;
andrewboyson 171:f708d6776752 103 DnsQueryIp4 = 0;
andrewboyson 172:9bc3c7b2cca1 104 Ip6AddrCopy(DnsQueryIp6, ip);
andrewboyson 171:f708d6776752 105 DnsQueryIsBusy = true;
andrewboyson 171:f708d6776752 106 _StartedMs = MsTimerCount;
andrewboyson 171:f708d6776752 107 _DnsProtocol = dnsProtocol;
andrewboyson 171:f708d6776752 108 _IpProtocol = ipProtocol;
andrewboyson 171:f708d6776752 109 _RecordType = DNS_RECORD_PTR;
andrewboyson 30:e34173b7585c 110 }
andrewboyson 30:e34173b7585c 111 static void logQuery()
andrewboyson 30:e34173b7585c 112 {
andrewboyson 43:bc028d5a6424 113 if (NetTraceNewLine) Log("\r\n");
andrewboyson 47:73af5c0b0dc2 114 LogTimeF("DnsQuery sent ");
andrewboyson 171:f708d6776752 115 DnsProtocolLog(_DnsProtocol);
andrewboyson 47:73af5c0b0dc2 116 Log(" request for ");
andrewboyson 171:f708d6776752 117 DnsRecordTypeLog(_RecordType);
andrewboyson 47:73af5c0b0dc2 118 Log(" ");
andrewboyson 30:e34173b7585c 119 if (DnsQueryIp4) //Reverse
andrewboyson 30:e34173b7585c 120 {
andrewboyson 47:73af5c0b0dc2 121 Ip4AddressLog(DnsQueryIp4);
andrewboyson 30:e34173b7585c 122 }
andrewboyson 30:e34173b7585c 123 else if (DnsQueryIp6[0])
andrewboyson 30:e34173b7585c 124 {
andrewboyson 172:9bc3c7b2cca1 125 Ip6AddrLog(DnsQueryIp6);
andrewboyson 30:e34173b7585c 126 }
andrewboyson 30:e34173b7585c 127 else //Forward
andrewboyson 30:e34173b7585c 128 {
andrewboyson 47:73af5c0b0dc2 129 Log(DnsQueryName);
andrewboyson 30:e34173b7585c 130 }
andrewboyson 47:73af5c0b0dc2 131 Log("\r\n");
andrewboyson 13:9cd54f7db57a 132 }
andrewboyson 171:f708d6776752 133 int DnsQueryPoll(int ipType, void* pPacket, int* pSize)
andrewboyson 13:9cd54f7db57a 134 {
andrewboyson 59:e0e556c8bd46 135 DnsHdrSetup(pPacket, *pSize);
andrewboyson 59:e0e556c8bd46 136
andrewboyson 171:f708d6776752 137 if (!DnsQueryIsBusy) return DO_NOTHING;
andrewboyson 172:9bc3c7b2cca1 138 if (_IpProtocol != EthProtocol) return DO_NOTHING; //Only use a poll from the required protocol
andrewboyson 171:f708d6776752 139 if (_DnsProtocol == DNS_PROTOCOL_UDNS && DhcpLocalIp == 0) return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 140
andrewboyson 57:e0fb648acf48 141 NetTraceHostCheckIp6(DnsQueryIp6);
andrewboyson 57:e0fb648acf48 142
andrewboyson 57:e0fb648acf48 143 if (DnsQueryTrace || NetTraceHostGetMatched()) logQuery();
andrewboyson 30:e34173b7585c 144
andrewboyson 13:9cd54f7db57a 145 static uint16_t id = 0;
andrewboyson 13:9cd54f7db57a 146 DnsHdrId = ++id;
andrewboyson 13:9cd54f7db57a 147 DnsHdrIsReply = false;
andrewboyson 171:f708d6776752 148 DnsHdrIsAuthoritative = false; //Added 12/12/2020
andrewboyson 13:9cd54f7db57a 149 DnsHdrIsRecursiveQuery = false;
andrewboyson 13:9cd54f7db57a 150
andrewboyson 13:9cd54f7db57a 151 DnsHdrQdcount = 1;
andrewboyson 13:9cd54f7db57a 152 DnsHdrAncount = 0;
andrewboyson 13:9cd54f7db57a 153 DnsHdrNscount = 0;
andrewboyson 13:9cd54f7db57a 154 DnsHdrArcount = 0;
andrewboyson 13:9cd54f7db57a 155
andrewboyson 13:9cd54f7db57a 156 DnsHdrWrite();
andrewboyson 13:9cd54f7db57a 157 char* p = DnsHdrData;
andrewboyson 13:9cd54f7db57a 158
andrewboyson 30:e34173b7585c 159 if (DnsQueryIp4 ) DnsNameEncodeIp4(DnsQueryIp4, &p);
andrewboyson 30:e34173b7585c 160 else if (DnsQueryIp6[0]) DnsNameEncodeIp6(DnsQueryIp6, &p);
andrewboyson 37:793b39683406 161 else DnsNameEncodePtr(DnsQueryName, &p);
andrewboyson 30:e34173b7585c 162
andrewboyson 30:e34173b7585c 163 *p++ = 0;
andrewboyson 171:f708d6776752 164 *p++ = _RecordType;
andrewboyson 171:f708d6776752 165 *p++ = _DnsProtocol == DNS_PROTOCOL_MDNS && MDNS_UNICAST ? 0x80 : 0; //Set the 15th bit (UNICAST_RESPONSE) to 1 if MDNS
andrewboyson 13:9cd54f7db57a 166 *p++ = 1; //QCLASS_IN = 1 - internet
andrewboyson 13:9cd54f7db57a 167
andrewboyson 13:9cd54f7db57a 168 *pSize = p - DnsHdrPacket;
andrewboyson 13:9cd54f7db57a 169
andrewboyson 13:9cd54f7db57a 170 DnsQueryIsBusy = false;
andrewboyson 38:cc8945857a0d 171
andrewboyson 171:f708d6776752 172 if (DnsQueryTrace || NetTraceHostGetMatched()) DnsHdrLog(_DnsProtocol);
andrewboyson 13:9cd54f7db57a 173
andrewboyson 37:793b39683406 174 int dest = DO_NOTHING;
andrewboyson 37:793b39683406 175
andrewboyson 171:f708d6776752 176 switch (_DnsProtocol)
andrewboyson 13:9cd54f7db57a 177 {
andrewboyson 37:793b39683406 178 case DNS_PROTOCOL_UDNS: dest = UNICAST_DNS; break; //IPv6 ==> NdpDnsServer; IPv4 ==> DhcpDnsServer
andrewboyson 37:793b39683406 179 case DNS_PROTOCOL_MDNS: dest = MULTICAST_MDNS; break;
andrewboyson 37:793b39683406 180 case DNS_PROTOCOL_LLMNR: dest = MULTICAST_LLMNR; break;
andrewboyson 13:9cd54f7db57a 181 default:
andrewboyson 171:f708d6776752 182 LogTimeF("DNS unknown query protocol %d\r\n", _DnsProtocol);
andrewboyson 13:9cd54f7db57a 183 return DO_NOTHING;
andrewboyson 13:9cd54f7db57a 184 }
andrewboyson 37:793b39683406 185
andrewboyson 57:e0fb648acf48 186 return ActionMakeFromDestAndTrace(dest, DnsQueryTrace || NetTraceHostGetMatched());
andrewboyson 13:9cd54f7db57a 187 }